Methods of quantifying the distribution of T1-201 in the myocardium were investigation by comparing regional distribution and washout of T1-201 by circumferential profile methods. In previous work, no account was taken of the large statistical fluctuations in the SPECT data. A simple solution to this problem was proposed and tested, involving the creation of an "error" image, in which each pixel value within this image represents the standard deviation of the SPECT T1-201 value. This error image could then be applied to the circumferential profile method to reduce the false positive rate and improve the adcurance of T1- 201 SPECT studies. The work resulted in a paper presented at the annual SNM entitled "SPECT Error Maps for Improving T1-201 Quantitation".